In conventional hair-curlers of this type, for example in U.S. Pat. No. 4,197,608 to Holly et al. issued Apr. 15, 1980, a heater is housed within a brush cylinder holding pipe which extends from a handle, and a brush cylinder is rotatably mounted like a sleeve around the brush cylinder holding pipe. Accordingly, not only is the brush cylinder holding pipe interposed between the brush cylinder and heater, but the radial distance between the inner circumferential surface of the brush cylinder and the confronting outer circumferential surface of the heater is so large as to inhibit the conduction of heat from the heater to the brush cylinder, leading to increased cost of operation or to a reduction of the hair-curling ability.